This invention relates to an improvement in the exercise shoe disclosed in U.S. Pat. No. 4,951,938 entitled EXERCISE SHOE, patented Aug. 28, 1990, Christopher J. B. Smith IV inventor and assigned to the same assignee as the present invention, and an improvement in the exercise shoe disclosed in design patent application Ser. No. 07/476,672, filed Feb. 8, 1990, entitled STRETCHING DEVICE FOR ROCKING THE FOOT TO STRETCH THE LOWER LEG, Christopher J. B. Smith IV inventor and assigned to the same assignee as the present invention. More particularly, this invention relates to an improved exercise shoe of the type disclosed in the aforementioned patent and patent application and wherein the range of rocking motion of such exercise shoe may be limited to one or more limited ranges of rocking motion, and still more particularly wherein such exercise shoe may be limited to one or more limited ranges of rearward rocking motion.
The exercise shoe disclosed in the above-identified patent and patent application, particularly patent application, is illustrated in FIG. 1 and identified by general numerical designation 10. The exercise shoe 10 includes a generally semi-circular base 12 for engaging a support surface 14, e.g. a floor, on which the exercise shoe 10 rocks. The exercise shoe 10 further includes a support member 16 extending generally upwardly from the base 12 and heel and ball support platforms 18 and 20 for respectively receiving the heel and ball of the foot of a person, and as may be noted from FIG. 1, the heel and ball support platforms are disposed at an acute included angle .beta. with respect to each other.
The exercise shoe 10 has a range of rocking motion, i.e. inherent range of rocking motion, .THETA.1 determined primarily by the arcuate or semi-circular length of the semi-circular base 12. Exercise shoe 10 has proven to be quite successful in stretching and strengthening various muscles and tendons in the lower leg and foot of a person. The person places a foot on the exercise shoe 10 with the heel of the person's foot residing on the heel platform 18 and with the ball of the person's foot residing on the ball platform 20; the person then rocks the exercise shoe alternately in the forward direction in the direction of the ball platform 10, and in the rearward direction in the, direction of the heel platform 18. Upon the exercise shoe 10 being rocked in the forward direction, plantarflexion occurs stretching and strengthening the anterior flexors, i.e. the anterior tibialis and extensor digitorum longus and to some extent the plantar fascia, and upon the exercise shoe 10 being rocked in the rearward direction, dorsiflexion occurs stretching and strengthening the plantar flexors, i.e. the gastrocnemius and soleus calf muscles, achilles tendon and plantar fascia.
In addition to being generally useful in stretching and strengthening the above-noted muscles and tendons, the exercise shoe 10 has been found to be particularly useful in post-operative rehabilitation of persons having experienced various surgical procedures on various of the above-noted muscles and tendons. In such post-operative rehabilitation, it has been found to be desirable to initially limit the person's foot to a limited range of rocking motion and to gradually increase the range of rocking motion to thereby gradually increasingly stretch and thereby gradually increasingly strengthen the operated muscles and tendons.
Accordingly, there exists a need in the exercise shoe art for a new and improved exercise shoe which may be provided with one or more limited ranges of rocking motion or, viewed alternately, which may be provided with a variable range of limited rocking motion, particularly a variable range of rocking motion.